Exterior sun visors which protrude from a vehicle roof forwardly of the windshield can effectively shade the vehicle cab interior and reduce the glare from the overhead rays of the sun. Aside from increasing passenger comfort and driver safety, visors may also extend the life of plastic dashboards and vehicle interiors by reducing cabin temperatures and limiting the exposure of the cabin interior to direct sunlight.
In addition to providing these functional benefits, some visors--sold as after-market accessories--provide a distinctive appearance which motorists may utilize to customize and distinguish their vehicles.
Early sun visors were fabricated of sheet metal and were hence quite heavy and advantageously rigid. As many early automobiles featured two-part segmented windshields having a central structural dividing bar, these early visors could be effectively supported by rigid metal struts bolted to the windshield side and center pillars.
Advances in automotive design and engineering substituted a one-piece curved windshield glass for the early segmented type and eliminated the central windshield pillar. Fiberglass and plastic fabrication techniques have allowed visors to be produced with weights much less than sheet metal visors. However, due to the extensive air flows over and around a moving vehicle, a visor is subjected to significant aerodynamic loads which must be countered by rigidly fixing the visor at multiple locations to the vehicle cab. Conventional sun visors are typically bolted to the vehicle cab roof at one or more central locations and at the roof sides. It has also been known to connect visor side ears to the front corner pillars. However, recent trends in automotive design have resulted in a substantial elimination of exposed corner pillars in many models.
Fiberglass and plastic visors typically are of a single sheet molded into a particular design configuration. Portions of the visor which are to be attached to the vehicle roof are placed flush with the roof and must be recessed beneath the overall visor surface or extended on tabs in many instances to permit portions of the visor to be elevated above the vehicle cab roof or to be spaced forwardly from the cab roof to permit oncoming air to pass beneath the visor. This flush mounting of the visor sheet material presents significant limitations to the appearance possibilities of such visors. Furthermore, the exposed heads of the attachment fasteners, even if painted to match the vehicle body color, are in dramatic contrast to the sleek fit and finish which is a desirable feature of modern automobiles.
Furthermore, as each automotive manufacturer produces vehicles with distinct cab dimensions and roof curvatures, separate and costly molds will typically need to be produced to form a distinct visor for each variety of motor vehicle.
What is needed is an attractive sun visor, the appearance features of which are not severally limited by the attachment mechanics, which is rigid and resistant to undesirable aerodynamic vibrations, and which may be produced for use on a wide variety of motor vehicles with minor manufacturing modifications.